Novice Question

I’m in the early stages of playing around with Audacity, and just made my first attempt at recording my speaking voice. I’m using the computer’s built-in soundcard (Realtek High Definition Sound) and a super el-cheapo dynamic mic labeled “Trans Continental Studios” (yes, it does have what appears to be an extra space) which I picked up a while back from one of the industrial surplus outfits. The cable that came with the mic has an XLR connector on the mic end and a two-conductor 1/4 inch plug on the other end. (I have no idea what, if anything, the third pin is hooked to.) I then use a 1/4 to 1/8 adaptor to plug it into the mic input on my computer’s front panel.

Obviously, this setup would not be adequate for studio-quality music recording, but it seems to achieve the objective of getting the sound into the computer. My question is, will I do any damage to any of the equipment with this setup?

Thanks.

Robert Rothman

No, with the caution that you connect the computer, then the microphone, not the other way 'round. Mic-In on a sound card supplies 5 volts on one of the internal connections as you slide the 1/8" home. It vanishes once the connection is pushed all the way in and it’s only there a split second, but it’s good not to get that voltage near the microphone. Never mess with the computer connections with the mic plugged in.

Your cable is more or less like this, right? Same number of metal rings?

http://kozco.com/tech/audacity/UnbalBalAdapter.jpg

Chances are grand that the XLR pin 2 is connected to the tip of the 1/4" and both pin 3 and pin 1 are connected to the shield. You might well ask, why bother with the three pins? What you have will probably work just dandy for the six feet and maybe up to 10 feet or so that you plan on using it. No quality problems at all – or very minimal ones. If you go much beyond that, the system will start to pick up household hum and buzz and other interference.

Professional and broadcast systems use all three pins: Pin 2 Main Signal, Pin 3 Correction Signal, and Pin 1 Protective Shield. If you have equipment that uses all three properly, you can connect hundreds of feet of cable with no ill effect.

And just because we know you don’t think much of your setup, it is exactly the system recommended to get started. You will find almost immediately that your room is the worst enemy. This recording was made into a very good microphone.

http://www.kozco.com/tech/audacity/clips/EchoSample.mp3

She just has echo problems, but you may have dogs barking, air conditioner rumble, traffic noise, etc. etc. Be assured that we can do little to nothing about all these problems. People post all the time looking for a way to reduce the MetroBus that got into their recording. Los Angeles Department of Transportation is now a permanent performer in your show.

Three of the four horsemen of sound recording have to do with live recording. 1, 2, and 4. If you play your cards right you can have all four.

– The Four Horsemen of Audio Recording (reliable, time-tested ways to kill your show)
– 1. Echoes and room reverberation (Don’t record the show in your mom’s kitchen.)
– 2. Overload and Clipping (Sound that’s too loud is permanently trashed.)
– 3. Compression Damage (Never do production in MP3.)
– 4. Background Sound (Don’t leave the TV on in the next room.)

We have people who record in a broom closet with quilts nailed to the walls and I’ve been known to build a studio out of furniture moving blankets as needed.

http://www.kozco.com/pictures/boothFinished/laptop-mic.jpg

We’re serious. This one problem is the primary reason people rent studio space.

And one parting shot. A New Microphone isn’t going to make you sound any better. Slightly less noisy, perhaps and maybe a little less forward or pronounced, but if you can’t sound very, very good with your present microphone and a good room, you can throw as much money as you want, it’s not going to get significantly better.

I’ve done temporary sound tracks for well-known commercial products with my built-in laptop microphone. The tracks were just OK quality, but the announcer (not me certainly) was very good and his voice fit right into the animations we were producing.

There is no Professional Announcer filter even if you find the one I wrote up as an April Fool gag.

Koz

http://forum.audacityteam.org/viewtopic.php?f=28&t=28341&start=0
Note the date.
Koz

Thanks.

I was not aware of the voltage provided as the plug is inserted into the computer, and I had in fact attached the cable to the mic first. However, it seemed to work, so hopefully it didn’t do any damage and in the future I will be careful to plug in the computer end of the cable first. I will also be sure to avoid using my other mic (also an el-cheapo model) which has a permanently attached cable.

The cable I have is basically what is shown in your picture; the only difference is that it has a 1/4" plug, rather than 1/8", so I use a 1/4 to 1/8 adaptor. The number of rings is the same, however, so its electrically identical.

I hope you’ll keep working on the Professional Announcer filter, although realistically that’s not really a problem for me. I’m certainly not a professional, but I do have a resonant speaking voice that often causes people to ask me whether I am one.


Rob Rothman

Headset systems like this have battery from the computer to run the microphone electronics.
http://www.kozco.com/tech/audacity/pix/PCHeadset.jpg

It’s connected like this (second illustration).
http://www.kozco.com/tech/audioconnectors/audioconnectors.html

Dynamic or moving coil microphones are remarkably robust. ElectroVoice had a demonstration where they would pound nails with one of their 635A microphones – and it still made specifications then they were done.

So no, you probably didn’t do anything serious, but it’s still a bad idea.

Koz